Hybrid micro guide catheter

ABSTRACT

A hybrid microguide catheter and method for making and using the same. The catheter may include a first tubular member and a second tubular member. The tubular members may be arranged so that the second tubular member extends distally beyond the first tubular member. Alternatively, the catheter may include a tubular body having a first opening and a second opening. The first opening may be positioned along the tubular body a distance from the second opening.

RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.13/025,381, filed Feb. 11, 2011, now U.S. Pat. No. 8,372,056, which is acontinuation of U.S. application Ser. No. 10/827,565, now U.S. Pat. No.7,887,529; the entire disclosures of which are incorporated herein byreference.

FIELD OF THE INVENTION

The present invention pertains to medical devices including catheters.More particularly, the present invention pertains to intravascularcatheters with a support and visualization portion and a distal accessportion.

BACKGROUND OF THE INVENTION

A wide variety of devices have been developed for medical use, forexample, intravascular use. Some of these devices include guidewires,catheters, and other such devices that each have certain features andcharacteristics. Among the known medical devices, each has certainadvantages and disadvantages. There is an ongoing need to providealternative designs and methods for making and using medical deviceswith desirable characteristics and features.

SUMMARY OF THE INVENTION

The invention provides design, material, and manufacturing methodalternatives for medical devices, for example, catheters. In at leastsome embodiments, the catheters include a support and visualizationportion and a distal access portion. The support and visualizationportion may be disposed near the proximal end region of the catheter andthe distal access portion may be disposed near the distal end region ofthe catheter. These and some of the other features and characteristicsof example embodiments are described in more detail below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is partial cross-sectional side view of an example catheterdisposed in the blood vessel;

FIG. 2 is a cross-sectional view of the catheter shown in FIG. 1;

FIG. 3 is a cross-sectional view of the catheter shown in FIG. 2 takenthrough line 3-3;

FIG. 4 is an alternative cross-sectional view of the catheter shown inFIG. 1;

FIG. 5 is a cross-sectional view of another example catheter;

FIG. 6 is a cross-sectional view of another example catheter;

FIG. 7 is a cross-sectional view of another example catheter;

FIG. 8 is a cross-sectional view of another example catheter;

FIG. 9 is a side view of another example catheter; and

FIG. 10 is a cross-sectional view of another example catheter.

DETAILED DESCRIPTION

The following description should be read with reference to the drawingswherein like reference numerals indicate like elements throughout theseveral views. The detailed description and drawings illustrate exampleembodiments of the claimed invention.

FIG. 1 is partial cross-sectional side view of an example catheter 10.Catheter 10 may include a proximal region 12 and a distal region 14. Inat least some embodiments, proximal region 12 is adapted and configuredso that it provides catheter 10 with a desirable amount of proximalstiffness. In addition, proximal region 12 may be used to enhancecatheter visualization. For example, proximal region 12 may include alumen 16 (better seen in FIG. 2) that can be used to infuse contrastmedia 18 (as a part of a standard fluoroscopy technique) into a bloodvessel 20. Of course, other substances can be passed through lumen 16 asdesired, including pharmacological agents.

In at least some embodiments, distal region 14 is adapted and configuredso that it provides catheter 10 with distal access to target vascularregions. For example, distal region 14 may extend deeper within bloodvessel 20 (which is, for example, exemplified by the narrowing of bloodvessel 20 in the lower half of FIG. 1) to an area near an intravascularlesion 22. Once positioned, a microcatheter 24 may be passed through alumen 26 defined in distal region 14. Microcatheter 24 may be any of anumber of different known microcatheters such as guide catheters,balloon catheters, cutting balloon catheters, atherectomy catheters,stent delivery catheters, filter delivery catheters, and the like, orany other suitable medical device. Advancing microcatheter 24 throughlumen 26 may include advancing microcatheter 24 over a guidewire 28 inthe manner typically used in the art. Guidewire 28 may be similar totypical guidewires used in the art.

Catheter 10 may include a first tubular member 30 and a second tubularmember 32 as illustrated in FIG. 2. According to this embodiment, thecombination of first tubular member 30 and second tubular member 32 maydefine proximal region 12. A portion of second tubular member 32 mayextend distally a distance D from first tubular member 30 in order todefine distal region 12. Distance D may reflect the distance between afirst opening 40 (through which, for example, contrast media or othersubstances can be infused) of first tubular member 30 and a secondopening 38 (through which, for example, a microcatheter can be advanced)of second tubular member 32. In some embodiments, the length of distanceD may be in the range about 1 to about 50 centimeters. In otherembodiments, the length of distance D may be in the range about 10 toabout 40 centimeters. In still other embodiments, the length of distanceD may be in the range about 20 to about 40 centimeters. It should benoted that the form and arrangement of tubular members 30/32 need not beexactly as stated, because a number of other arrangements arecontemplated. For example, second tubular member 32 need not be disposedas illustrated at proximal region 12, as it may be positioned anywherein lumen 16.

Tubular members 30/32 may be made from any suitable material such asmetals, metal alloys, metal-polymer composites, polymers, and the likeor any other suitable material. In some embodiments, tubular members30/32 have the same or similar material composition. In otherembodiments, tubular members 30/32 have different material compositions.Below are some lists of materials that can be used to manufacturetubular members 30/32. The lists are not intended to be exhaustive or tobe limiting. Some examples of suitable metals and metal alloys includestainless steel, such as 304V, 304L, and 316LV stainless steel; mildsteel; nickel-titanium alloy such as linear-elastic or super-elasticnitinol, nickel-chromium alloy, nickel-chromium-iron alloy, cobaltalloy, tungsten or tungsten alloys, MP35-N (having a composition ofabout 35% Ni, 35% Co, 20% Cr, 9.75% Mo, a maximum 1% Fe, a maximum 1%Ti, a maximum 0.25% C, a maximum 0.15% Mn, and a maximum 0.15% Si),hastelloy, monel 400, inconel 825, or the like; other Co—Cr alloys;platinum enriched stainless steel; or other suitable material.

Some examples of suitable polymers may include polytetrafluoroethylene(PTFE), ethylene tetrafluoroethylene (ETFE), fluorinated ethylenepropylene (FEP), polyoxymethylene (POM, for example, DELRIN® availablefrom DuPont), polybutylene terephthalate (PBT), polyether block ester,polyurethane, polypropylene (PP), polyvinylchloride (PVC),polyether-ester (for example, a polyether-ester elastomer such asARNITEL® available from DSM Engineering Plastics), polyester (forexample, a polyester elastomer such as HYTREL® available from DuPont),polyamide (for example, DURETHAN® available from Bayer or CRISTAMID®available from Elf Atochem), elastomeric polyamides, blockpolyamide/ethers, polyether block amide (PEBA, for example, availableunder the trade name PEBAX®), silicones, polyethylene (PE), Marlexhigh-density polyethylene, Marlex low-density polyethylene, linear lowdensity polyethylene (for example, REXELL®), polyethylene terephthalate(PET), polyetheretherketone (PEEK), polyimide (PI), polyetherimide(PEI), polyphenylene sulfide (PPS), polyphenylene oxide (PPO),polysulfone, nylon, perfluoro(propyl vinyl ether) (PFA), other suitablematerials, or mixtures, combinations, copolymers thereof, polymer/metalcomposites, and the like. In some embodiments, tubular members 30/32 canbe blended with a liquid crystal polymer (LCP). For example, the mixturecan contain up to about 5% LCP. This has been found to enhancetorqueability.

In some embodiments, a coating, for example, a lubricious, ahydrophilic, a protective, or other type of coating may be applied overportions or all of tubular members 30/32, or other portions of catheter10. Hydrophobic coatings such as fluoropolymers provide a dry lubricitywhich improves catheter handling and device exchanges. Lubriciouscoatings improve steerability and improve lesion crossing capability.Suitable lubricious polymers are well known in the art and may includesilicone and the like, hydrophilic polymers such as high-densitypolyethylene (HDPE), polytetrafluoroethylene (PTFE), polyarylene oxides,polyvinylpyrolidones, polyvinylalcohols, hydroxy alkyl cellulosics,algins, saccharides, caprolactones, and the like, and mixtures andcombinations thereof. Hydrophilic polymers may be blended amongthemselves or with formulated amounts of water insoluble compounds(including some polymers) to yield coatings with suitable lubricity,bonding, and solubility. Some other examples of such coatings andmaterials and methods used to create such coatings can be found in U.S.Pat. Nos. 6,139,510 and 5,772,609, which are incorporated herein byreference.

In some embodiments, first tubular member 30 and/or second tubularmember 32 may include one or more cuts or grooves formed therein (e.g.,by micro-machining). Micro-machining tubular members 30/32 may bedesirable because it allows a stiffer starting material (e.g., stainlesssteel, nickel-titanium alloy, etc.) to be used in the manufacturing oftubular members 30/32 that can be smaller, thinner, or otherwise have alower profile than less stiff materials. This stiff material can then bemicro-machined in order to impart the desired level of flexibility.Further discussion on the use of forming cuts, slots, or grooves as wellmicro-machining can be found in U.S. Patent Publication No.2004/0193140, in U.S. Pat. No. 6,428,489, and in U.S. Patent PublicationNo. 2002/0013540, the entire disclosures of which are hereinincorporated by reference.

Tubular members 30/32 may be coupled to one another in a number ofdifferent manners. For example, FIG. 3 illustrates that tubular members30/32 may be coupled by directly securing first tubular member 30 withsecond tubular member 32. For example, an outer surface 36 of tubularmember 32 may be attached to an inner wall 34 of tubular member 30. Theattachment may be manifested through the use of an adhesive, thermalbond, weld, mechanical connector, or any other suitable means. Inalternative embodiments, tubular members 30/32 may have a differentarrangement that may vary the manner in which they are bonded. Forexample, tubular member 32 could be coaxially disposed within tubularmember 30, irregularly disposed within tubular member 30, includeregions disposed in differing manner, disposed along the exterior oftubular member 30, and the like, or disposed in any other suitablearrangement.

Alternatively, tubular members 30/32 may be coupled during manufacturingvia an extrusion process as seen in FIG. 4. According to thisembodiment, catheter 10 (indicated in FIG. 4 as catheter 10′) can beco-extruded so as to define “dual lumens” (i.e., lumens 16/26) alongproximal region 12 and a single lumen (i.e., lumen 26) along distalregion 14. The dual lumen proximal region 12 may define first tubularmember 30 and second tubular member 32. The single lumen proximal region14 would, therefore, define distance D of second tubular member 32extending distally from proximal region 12. These alternativearrangements may entail alternative bonding strategies. In someembodiments, co-extrusion may take place in concert with the addition ofother support structures (such as those seen in FIG. 5) or in theabsence of such structures.

As suggested above, catheter 10 may take the form of a hybrid “microguide” catheter. This nomenclature reflects the fact that catheter 10may be a hybridization of some of the desirable characteristics andstructure of typical microcatheters with some of the desirablecharacteristics and structure of typical guide catheters. For example,catheter 10 includes proximal region 12 that may have a proximalstiffness (similar to that of guide catheters) so as to provide asuitable level of pushability and torqueability when advancing catheter10 through the vasculature. In addition, catheter 10 includes distalregion 14 that can provide distal access to vascular targets and mayhave a distal flexibility (similar to that of microcatheters) suitablefor navigating the tortuous vasculature. Distal region 14 can also serveas a guidewire or guiding structure over which other medical devices canbe passed.

Because of the arrangement which second tubular member 32 extendsdistally from first tubular member 30, catheter 10 may be well suitedfor neurological applications. This is because the length (i.e.,distance D) of tubular member 32 is typically long enough and suitablyflexible so that it can navigate into the target neurologicalvasculature while proximal region 12 remains disposed in a more proximallocation away from the head. Thus, the larger bore proximal region 12can remain in larger vessels, while the smaller bore distal region 14can advance through the smaller, more sensitive neuro-vasculature.Moreover, because first opening 40 of first tubular member 30 is setback distance D from second opening 38, contrast media can still beinfused into the blood vessel (via lumen 16) that will travel within theblood stream toward the target site. Distance D may range from about 10cm. to about 50 cm. For a preferred use in neurological applications,distance D is about 20 cm. to about 40 cm.

It should be noted that in addition to contrast media, a number ofdifferent substances may be passed through lumen 16. The substance maybe generally described as a drug, chemotherapeutic, antibiotic, etc.Some examples of appropriate substances may include anti-thrombogenicagents and/or anticoagulants such as heparin, heparin derivatives,urokinase, and PPack (dextrophenylalanine proline argininechloromethylketone) D-Phe-Pro-Arg chloromethyl keton, an RGDpeptide-containing compound, antithrombin compounds, platelet receptorantagonists, anti-thrombin antibodies, anti-platelet receptorantibodies, aspirin, prostaglandin inhibitors, platelet inhibitors, andtick antiplatelet peptides; anti-proliferative agents such as enoxaprin,angiopeptin, or monoclonal antibodies capable of blocking smooth musclecell proliferation, hirudin, and acetylsalicylic acid; anti-inflammatoryagents such as dexamethasone, prednisolone, corticosterone, budesonide,estrogen, sulfasalazine, and mesalamine;antineoplastic/antiproliferative/anti-miotic agents such as paclitaxel,5-fluorouracil, cisplatin, vinblastine, vincristine, epothilones,endostatin, angiostatin and thymidine kinase inhibitors; anestheticagents such as lidocaine, bupivacaine, and ropivacaine; vascular cellgrowth inhibitors such as growth factor inhibitors, growth factorreceptor antagonists, transcriptional repressors, translationalrepressors, replication inhibitors, inhibitory antibodies, antibodiesdirected against growth factors, bifunctional molecules consisting of agrowth factor and a cytotoxin, bifunctional molecules consisting of anantibody and a cytotoxin; cholesterol-lowering agents; vasodilatingagents; agents which interfere with endogenous vascoactive mechanisms;anti-sense DNA and RNA; and DNA coding for (and the correspondingproteins) anti-sense RNA, tRNA or rRNA to replace defective or deficientendogenous molecules, angiogenic factors including growth factors suchas acidic and basic fibroblast growth factors, vascular endothelialgrowth factor, epidermal growth factor, transforming growth factor a andB, platelet-derived endothelial growth factor, platelet-derived growthfactor, tumor necrosis factor a, hepatocyte growth factor and insulinlike growth factor, cell cycle inhibitors including CD inhibitors,thymidine kinase (“TK”) and other agents useful for interfering withcell proliferation, and the family of bone morphogenic proteins(“BMP's”) including BMP-2, BMP-3, BMP-4, BMP-5, BMP-6 (Vgr-1), BMP-7(OP-1), BMP-8, BMP-9, BMP-10, BMP-11, BMP-12, BMP-13, BMP-14, BMP-15,BMP-16, “hedgehog” proteins.

FIG. 5 illustrates another example catheter 110. Catheter 110 is similarto catheter 10 except that first tubular member 130 and/or secondtubular member 132 may include a variety of additional structuralelements. For example, first tubular member 130 may include a coil 142,a braid 144, or multiples of either or both. Although coil 142 and braid144 are depicted as being disposed at proximal region 112, this is notintended to be limiting as these structures could be disposed atessentially any position along first tubular member 130. Similarly,second tubular member 132 may also include a coil 146, a braid 148, ormultiples of either or both. Again, the position of coil 146 and braid148 may vary so as to be included at essentially any position alongsecond tubular member 132.

Coils 142/146 and/or braids 144/148 may be similar to those typicallyseen in the art and can be made from any of the materials disclosedherein. Generally, coils 142/146 and/or braids 144/148 are provided as areinforcing structure that can, for example, stiffen and/or strengthenthe structure to which they are coupled. Because the distribution ofsupport structures (i.e., coils 142/146, braids 144/148, etc.) can varyalong the lengths of tubular members 130/132, regions having differentflexibilities can be defined along catheter 110. Other structuralmodifications may also be present such as tapering of tubular members130/132 in a regular, irregular, step-wise, or other manner. In someembodiments, coils 142/146 and/or braids 144/148 can be added subsequentan extrusion process or prior to an extrusion process (which wouldextrude another layer or material over coils 142/146 and/or braids144/148). Of course, coils 142/146 and/or braids 144/148 are optionalfeatures that may be omitted from extrusion processes or other cathetermanufacturing processes.

Coils 142/146 and/or braids 144/148 can also be used for other reasonsincluding visualization. For example, coils 142/146 and/or braids144/148 may be made from or otherwise include a radiopaque material.Radiopaque materials are understood to be materials capable of producinga relatively bright image on a fluoroscopy screen or another imagingtechnique during a medical procedure. This relatively bright image aidsthe user of catheter 10 in determining its location. Some examples ofradiopaque materials can include, but are not limited to, gold,platinum, palladium, tantalum, tungsten alloy, plastic material loadedwith a radiopaque filler, and the like. Likewise, other radiopaquestructures may also be incorporated into catheter 10, such as markerbands 150.

FIG. 6 illustrates another example catheter 510. Catheter 510 is similarto other catheters described herein except that first tubular member 530and second tubular member 532 are arranged side-by-side and each includetapered regions. For example, first tubular member 530 may includetapered region 554 that tapers from “thick” to “thin” in the distaldirection and second tubular member 532 may include tapered region 556that tapers from “thin” to “thick” in the distal direction and mateswith tapered region 554. This arrangement allows the flexibilitycharacteristics of tubular member 530 to blend with those of tubularmember 532. For example, tubular member 530 may be less flexible thantubular member 532 so that the overlapping tapered arrangement blendsthese flexibilities and creates a smooth transition in flexibility.Additionally, the overlapping arrangement may also allow for torquecontrol or torqueability to be blended or otherwise progressivelycontrolled.

The length, steepness or pitch, and position of tapered regions 554/556may vary. For example, tapered regions 554/556 could extend along anyportion (or all) of the length of catheter 510. In addition, anysuitable steepness or abruptness in the amount of tapering can beutilized. Although overlapping tapered regions 554/556 are shown in FIG.6 as being disposed at proximal portion 512, this feature is notintended to be limiting. For example, overlapping tapered regions554/556 could be disposed at distal portion 514 or both proximal portion512 and distal portion 514. Moreover, a number of additional overlappingtapered regions may be defined at essentially any position alongcatheter 510.

FIG. 7 illustrates another example catheter 610. Catheter 610 is similarto other catheters described herein except that only one tubular member,for example tubular member 630, includes a tapered region 658. Taperedregion 658 may help blend the flexibilities of tubular members 630/632as well add a number of other significant features as described above.Tapered region 658 may vary as described above in relation to taperedregions 554/556. For example, tapered region 658 may be disposed alongproximal portion 612, distal portion 614, combinations thereof, or atany suitable location. Moreover, tapered region 658 could also beembodied by a taper defined in tubular member 632.

FIG. 8 illustrates another example catheter 210. Catheter 210 is similarto other catheters described herein except that first tubular member 230and second tubular member 232 are disposed parallel to one another withfirst tubular member 230 being truncated relative to second tubularmember 232. According to this embodiment, tubular members 230/232 can besecured together via any typical bonding technique (including thosedisclosed herein) or secured together with a mechanical connector suchas a sheath 252. Generally, sheath 252 is disposed at proximal region212 of catheter 210 and extends around at least a portion of bothtubular members 230/232. The form and material composition of sheath 252may vary. For example, sheath 252 may be made from a polymer such asthose listed above. In a manner similar to the other disclosedembodiments, second tubular member 232 extends distally beyond firsttubular member 230 to define distal region 214. The length of the distalregion D can be selected as to discussed above, especially forneurological applications.

FIG. 9 illustrates another example catheter 310. Catheter 310 includesproximal region 312 and distal region 314. The form of catheter 310differs from the other catheters disclosed herein because rather thanincluding multiple tubes, catheter 310 is generally formed of asingular, tapered tubular member. The taper defines variable outerdiameter proximal and distal regions 312/314. Proximal region 312 mayhave an outer diameter suitable to impart the desired amount ofstiffness. By virtue of being narrower, distal region 314 may impart thedesired distal flexibility characteristics and distal access abilitiesdescribed above. These and other features can be varied in a number ofways, such as by adding additional structures (such as coils and/orbraids as seen in FIG. 3) to vary the flexibility. In some embodiments,distal region 314 may ultimately taper so that the inner diameter ofdistal region 314 corresponds to about the outer diameter of themicrocatheter intended to extend therethrough. This feature canessentially “seal” catheter 310 so that contrast media can beessentially prevented from passing through opening 338. Alternatively,distal region 314 may remain slightly larger than the microcatheter sothat fluid can pass through opening 338.

Similar to the other disclosed embodiments, catheter 310 includes firstopening 340 and second opening 338 that are separated by a distance D′.Again, separating openings 340/338 by distance D′ allows contrast mediaor other substances to be infused through catheter 310 and into theblood vessel through opening 340 and allows a microcatheter or othermedia device to be advanced through opening 338. This feature may bedesirable, for example, in neurological applications where thevasculature may shift from relatively large vessels to small and/orsensitive vessels at or near the to neurological treatment site.

As described above, catheter 310 may be a singular tubular member.However, this need not be the case. For example, FIG. 10 illustratesanother catheter 410 that is similar to catheter 310 except that itincludes a first tubular member 430 and a second tubular member 432.According to this embodiment, proximal portion 412 may include bothtubular members 430/432 similarly to some of the other embodimentsdescribed above. Tubular member 430 may terminate at opening 440 whereastubular member 432 may terminate at opening 438 (which are separated adistance D′ in essentially the same manner as shown in FIG. 9). Thisallows catheter 410 to function in a manner that is substantiallysimilar to catheter 310.

It should be understood that this disclosure is, in many respects, onlyillustrative. Changes may be made in details, particularly in matters ofshape, size, and arrangement of steps without exceeding the scope of theinvention. The invention's scope is, of course, defined in the languagein which the appended claims are expressed.

What is claimed is:
 1. A catheter, comprising: an inner tube having adistal end, an outer surface, and defining an infusion lumen; an outertube having a distal end, an inner surface, and defining a catheterlumen; and wherein the outer surface of the inner tube is bonded to theinner surface of the outer tube; and wherein the distal end of the innertube extends distally beyond the distal end of the outer tube.
 2. Thecatheter of claim 1, wherein the outer tube includes a tapered outersurface.
 3. The catheter of claim 1, wherein the inner tube, the outertube, or both have a plurality of slots formed therein.
 4. The catheterof claim 1, wherein the inner tube, the outer tube, or both have areinforcing coil disposed therein.
 5. The catheter of claim 1, whereinthe inner tube, the outer tube, or both have a reinforcing braiddisposed therein.
 6. The catheter of claim 1, wherein the distal end ofthe inner tube extends 10 centimeters or more distally beyond the distalend of the outer tube.
 7. The catheter of claim 1, wherein a portion ofthe inner tube is disposed coaxially within the outer tube.
 8. Thecatheter of claim 1, wherein: a first portion of the inner tube isdisposed coaxially within the outer tube; and a second portion of theinner tube is disposed non-coaxially within the outer tube.
 9. Thecatheter of claim 1, further comprising: a microcatheter extendingthrough the catheter lumen.
 10. A hybrid micro guide catheter,comprising: a catheter tube having an outer surface and a microcatheterlumen; a microcatheter extending through the microcatheter lumen, themicrocatheter being configured to access a neurovascular portion of theanatomy of a patient; and a contrast media tube having an inner surface;and wherein the outer surface of the catheter tube is secured to theinner surface of the contrast media tube.
 11. The hybrid micro guidecatheter of claim 10, wherein the contrast media tube includes a taperedouter surface.
 12. The hybrid micro guide catheter of claim 10, whereinthe catheter tube, the contrast media tube, or both have a plurality ofslots formed therein.
 13. The hybrid micro guide catheter of claim 10,wherein the catheter tube, the contrast media tube, or both have areinforcing coil disposed therein.
 14. The hybrid micro guide catheterof claim 10, wherein the catheter tube, the contrast media tube, or bothhave a reinforcing braid disposed therein.
 15. The hybrid micro guidecatheter of claim 10, wherein a distal end of the catheter tube extends10 centimeters or more distally beyond a distal end of the contrastmedia tube.
 16. The hybrid micro guide catheter of claim 10, wherein aportion of the catheter tube is coaxial within the contrast media tube.17. The hybrid micro guide catheter of claim 10, wherein the outersurface of the catheter tube is secured to the inner surface of thecontrast media tube with a thermal bond.
 18. The hybrid micro guidecatheter of claim 10, wherein the outer surface of the catheter tube issecured to the inner surface of the contrast media tube with an adhesivebond.
 19. The hybrid micro guide catheter of claim 10, wherein the outersurface of the catheter tube is secured to the inner surface of thecontrast media tube with a mechanical connector.
 20. A method for usinga catheter including a first tubular member having a proximal endregion, a distal end region, and a first lumen extending at leastpartially therethrough, a second tubular member coupled to the firsttubular member, the second tubular member having a proximal end region,a distal end region, and a second lumen extending at least partiallytherethrough, and wherein the distal end region of the second tubularmember extends distally beyond the distal end region of the firsttubular member, comprising: disposing the catheter in a blood vessel sothat the distal end region of the second tubular member is disposedadjacent a target region; infusing contrast media into the blood vesselthrough the first lumen of the first tubular member; and advancing amicrocatheter through the second lumen of the second tubular member toaccess a neurovascular portion of the anatomy of a patient.